A Foot Pedal To Supplement Your Keyboard

March 18, 2025 by Lewin Day 24 Comments

It’s 2025, and you’re still probably pressing modifier keys on your keyboard like a… regular person. But it doesn’t have to be this way! You could use foot pedals instead, as [Jan Herman] demonstrates.

Now, if you’re a diehard embedded engineer, you might be contemplating your favorite USB HID interface chip and how best to whip up a custom PCB for the job. But it doesn’t have to be that complicated! Instead, [Jan] goes for an old school hack—he simply ripped the guts out of an cheap USB keyboard. From there, he wired up a few of the matrix pads to 3.5 mm jack connectors, and put the whole lot in a little metal project box. Then, he hooked up a few foot pedal switches with 3.5 mm plugs to complete the project.

[Jan] has it set up so he can plug foot pedals in to whichever keys he needs at a given moment. For example, he can plug a foot pedal in to act as SPACE, ESC, CTRL, ENTER, SHIFT, ALT, or left or right arrow. It’s a neat way to make the project quickly reconfigurable for different productivity tasks. Plus, you can see what each pedal does at a glance, just based on how it’s plugged in.

It’s not an advanced hack, but it’s a satisfying one. We’ve seen some other great builds in this space before, too. If you’re cooking up your own keyboard productivity hacks, don’t hesitate to let us know!

Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Cheesy Keyboard

March 18, 2025 by Kristina Panos 4 Comments

Let’s just kick things off in style with the fabulously brutalist Bayleaf wireless split from [StunningBreadfruit30], shall we? Be sure to check out the wonderful build log/information site as well for the full details.

Image by [StunningBreadfruit30] via reddit

Here’s the gist: this sexy split grid of beautiful multi-jet fusion (MJF) keycaps sits on top of Kailh PG1316S switches. The CNC-machined aluminium enclosure hides nice!nano boards with a sweet little dip in each one that really pull the keyboard together.

For the first serious custom build, [StunningBreadfruit30] wanted a polished look and finish, and to that I say wow, yes; good job, and nod enthusiastically as I’m sure you are. Believe it or not, [StunningBreadfruit30] came into this with no CAD skills at all. But it was an amazing learning experience overall, and an even better version is in the works.

I didn’t read the things. Is it open-source? It’s not, at least not at this time. But before you get too-too excited, remember that it cost $400 to build, and that doesn’t even count shipping or the tools that this project necessitated purchasing. However, [StunningBreadfruit30] says that it may be for sale in the future, although the design will have an improved sound profile and ergonomics. There’s actually a laundry list of ideas for the next iteration. Continue reading “Keebin’ With Kristina: The One With The Cheesy Keyboard” →

Build Your Own Air Mouse, Okay?

March 17, 2025 by Lewin Day 7 Comments

Are you using a desk mouse like some kind of… normal computer user? Why, beg the heavens? For you could be using an air mouse, of your very own creation! [Misfit Maker] shows the way. Check out what he made in the video below.

An air mouse is a mouse you use in the air—which creates at least one major challenge. Since you’re not sliding along a surface, you can’t track the motion by mechanical friction like a ball mouse or by imaging as in an optical mouse. Instead, this build relies on a gyroscope sensor to track motion and translate that into pointer commands. The build relies on an ESP32-C3 as the microcontroller at the heart of things. It communicates with an MPU6050 gyroscope and accelerometer to track motion in space. It then communicates as a human interface device over Bluetooth, so you can use it with lots of different devices. The mouse buttons—plus media control buttons—are all capacitive touch-sensitive, thanks to an MPR121 touch sensor module.

There’s something neat about building your own tools to interface with the machines, almost like it helps meld the system to your whims. We see a lot of innovative mouse and HID projects around these parts.

Continue reading “Build Your Own Air Mouse, Okay?” →

Building A Ten-Hundred Key Computer Word-Giving Thing

March 14, 2025 by Dan Maloney 18 Comments

From the styling of this article’s title, some might assume that the Hackaday editors are asleep at the switch this fine day. While that might be true — it’s not our turn to watch them — others will recognize this tortured phrasing as one way to use the 1,000 most commonly used words in the English language to describe a difficult technical project, such as [Attoparsec]’s enormous and enormously impractical ten-hundred word keyboard.

While the scale of this build is overwhelming enough, the fact that each key delivers a full word rather than a single character kind of throws the whole keyboard concept out the window. The 60×17 matrix supports the 1,000 most common English words along with 20 modifier keys, which allow a little bit of cheating on the 1-kiloword dictionary by letting you pluralize a word or turn it into an adjective or adverb. Added complexity comes from the practical limits of PCB fabrication, which forces the use of smaller (but still quite large) PCBs that are connected together. Luckily, [Attoparsec] was able to fit the whole thing on five identical PCBs, which were linked together with card-edge connectors.

The list of pain points on this six-month project is long, and the video below covers them all in detail. What really stood out to us, though, was the effort [Attoparsec] put into the keycaps. Rather than 3D printing his own, he used dye sublimation to label blank keycaps with the 1,000 words. That might sound simple, but he had to go through a lot of trial and error before getting a process that worked, and the results are quite nice. Another problem was keeping the key switches aligned while soldering, which was solved with a 3D printed jig. We also appreciate the custom case to keep this keyboard intact while traveling; we’re going to keep that build-your-own road case service in mind for future projects.

This mega-keyboard is a significant escalation from [Attoparsec]’s previous large keyboard project. The results are pretty ridiculous and impractical, but that’s just making us love it more. The abundance of tips and tricks for managing a physically expansive project are just icing on the cake.

Continue reading “Building A Ten-Hundred Key Computer Word-Giving Thing” →

Keebin’ With Kristina: The One With The Batwing Typewriter

March 11, 2025 by Kristina Panos 8 Comments

[Alex] of YouTube channel [EastMakes] wrote into tell me about his fantastic QWERTY ‘hexpansion’ board for the 2024 EMF Tildagon badge, and [Alex], I’m super glad you did. The system works!

Let’s back up a bit. Essentially, the idea is to have a badge that can be used beyond a single camp, with the creation of expansion boards being the other main attraction. Our own [Jenny List] covered the badge in detail back in June 2024 when she got her hands on one.

A pair of hands holds the 2024 EMF Tildagon badge with a QWERTY keyboard Hexpansion built by [EastMakes]. — Image by [EastMakes] via YouTube

[Alex] started by importing the Tildagon into Fusion360 and designing a way for the keyboard to attach to it physically. He then modeled the keyboard after the Blackberry types that can be found on Ali using the official EMF buttons established in earlier badges.

This QWERTY hexpansion is based on the RP2040, which is soldered around back and visible through the 3D-printed backplate. In order for the 90°-oriented board to align with the… not-90° connector, [Alex] built a little meander into the PCB.

The default OS on the Tildagon doesn’t know natively what to do with the serial messages from the keyboard, so [Alex] wrote an application that reads them in and decodes them. Be sure to check out the build and walk-through video after the break.

Continue reading “Keebin’ With Kristina: The One With The Batwing Typewriter” →

Custom Touchpad PCBs Without The Pain

March 6, 2025 by Jenny List 11 Comments

Many of us use touch pads daily on our laptops, but rarely do we give much thought about what they really do. In fact they are a PCB matrix of conductive pads, with a controller chip addressing it and sensing the area of contact. Such a complex and repetitive pattern can be annoying to create by hand in an EDA package, so [Timonsku] has written a script to take away the work.

It starts with an OpenSCAD script (originally written by Texas Instruments, and released as open source) that creates a diamond grid, which can be edited to the required dimensions and resolution. This is then exported as a DXF file, and the magic begins in a Python script. After adjustment of variables to suit, it finishes with an Eagle-compatible board file which should be importable into other EDA packages.

We’ve never made a touchpad ourselves, but having dome other such repetitive PCB tasks we feel the pain of anyone who has. Looking at this project we’re struck by the thought that its approach could be adapted for other uses, so it’s one to file away for later.

This isn’t the first home-made touchpad project we’ve brought you.

Why 56k Modems Relied On Digital Phone Lines You Didn’t Know We Had

March 6, 2025 by Lewin Day 51 Comments

If you came of age in the 1990s, you’ll remember the unmistakable auditory handshake of an analog modem negotiating its connection via the plain old telephone system. That cacophony of screeches and hisses was the result of careful engineering. They allowed digital data to travel down phone lines that were only ever built to carry audio—and pretty crummy audio, at that.

Speeds crept up over the years, eventually reaching 33.6 kbps—thought to be the practical limit for audio modems running over the telephone network. Yet, hindsight tells us that 56k modems eventually became the norm! It was all thanks to some lateral thinking which made the most of the what the 1990s phone network had to offer.

Continue reading “Why 56k Modems Relied On Digital Phone Lines You Didn’t Know We Had” →